Radio-frequency (RF) transmitters and receivers having multiple high frequency channels that are frequency-locked or jointly modulated are useful for a variety of applications. These applications include remote sensing, radar, and airport security screening systems. High-speed data links, high-speed wireless local area networks, and broadband Internet access systems also can benefit from high frequency multi-channel RF implementations.
Nevertheless, designing such multiple interlocked RF channels presents a number of challenges. RF transmitter and receiver systems are typically implemented on Printed Circuit Board (PCB), and the antennas of many systems are implemented using traces directly on the underlying PCB. Yet in some applications these PCB antenna designs limit scalability and flexibility and make increasing or decreasing the number of channels more difficult. Furthermore, for a given PCB material, energy losses increase with increasing channel frequency and trace length. Regardless of antenna design, such increasing energy losses would be experienced if a single Local Oscillator (LO) operating at high radio frequencies were to be shared between separate channels to provide the mechanism of frequency-locking or jointly modulating the channels.